Molded laminated article



G. H. DAVIS MOLDED LAMINATED ARTICLE Feb, 17, 1925 'Filed sept. '29, 1922 @13 A() ma y Patented Feb. I7, i925.

GEORGEvHOWLETT DAVIS, F ORANGE, NEW JERSEY.

'MOLDED LAMINATED ARTIGL'E.

Application led September 29, 1922. Serial No. 591,300.

l To all whom t may concer/n.: l

Be it known that I, GEORGE HowLErr DAVIS, a citizen of the United States, residing at'Orange, in the county of Essex and 'K 5 State of New ersey, have invented certain new and useful Improvements in Molded Laminated Articles, of which the following is\a specication. I l

This invention relates to molded laminatedarticles, and more particularly to articles formed of a plurality of sheets of fibrous material, such aspaper or cardboard.

While the invention is particularly applicable to and will be described as embodied .15 ina phonograph record, it is equally ap# plicable to other articles.

Numerous attempts have heretofore been I made to produce a satisfactory vphonograph disc record having a body formed of fibrous material, such as paper or the like, but records of this character heretofore produced have been subject to the grave defect that they tend to warp and become distorted out of a true plane. As is obvious, such warpng renders the record commercially valueess. l.

This warping or distortion of records with a paper base is largely due to the absorption of moisture by the paper'stock and its consequent uneven expansion. Moreover, the

\ coefficient of expansion of the paper body is often different from that of the veneering of thermoplastic material with which the body is covered and which carries the impression 4of the sound waves, such variation in the coeicients of expansion havinga further tendency to cause warping or twisting of the record.

-The primary object of the present invention, therefore, is to prevent such warping or twisting, and to provide a disc record or like article which will remain perfectly fiat and true indefinitely, under all atmospheric conditions.

`lhonograph disc records, as heretofore constructed, have been more or less fragile and easily broken. It is, therefore, another object' of the present invention to provide a record o1' like article which shall be practically indestructible underA ordinary handlin and which will successfully withstan shipment through the mails without elaborate protective packing. To this end, I contemplate the construction of a record or like article which shall bhe bendable or flexible to a high degree, so that it will readily yield to pressure and when released, will resume its original shape.

I have discovered that the above results may be attained by building up the base or body of the record or like article from layers of paper stock of different characteristics, and particularly by employing an inner or central layer of relatively soft porous absorbent material.

In order that the invention may be more clearly understood, reference is had to the accompanying drawing, forming part of this specification, and in which:

Fig. l is a transverse central section through al record constructed in accordance with the preferred form of my invention; an

Fig. 2 is a similar view showing a somewhat modified construction.

Referring to the drawings in detail, I construct my improved record or similar article as follows. I first take a disc or sheet of soft, flexible, absorbent, porous, fibrous material 1, such as blotting paper. To each side of this central layer or core, I next glue or cement a disc or layer 2 of a harder, denser and less porous, fibrous material such as cardboard. The particularv grade of cardboard which I have found in practice tobe especially suitable for this purpose, is that known in the trade as pattern board, and both this and the central core are pref- Verably about two hundredths of an inch in thickness. The glue or cement which I preferably employ for uniting the central core to these outer layers is of such a nature as not to penetrate or impregnate the paper to any substantial extent, so that the central layer or core retains, to a large degree, its

soft, porous and absorbent properties.

The outer surfaces of the dense outside layers 2 are preferably well calendered so that they are smooth and compact. This is desirable in order that they may not absorb too large a quantity of the thermoplastic veneerin which is applied to them.

This t ermoplastic veneering or, surface coating is designated by the reference numeral 3, and may consist of suitable mixtures of shellac and china clay, or other wel] known materials usually employed in the manufacture of this type of. phonograph records. This material is applied by either dusting or painting on, and the sound wave gij record is impressed therein by means of a two outer'layers, being disposed synpn-etrically, one on' each sidel of the central absorbent layer, tend to balance each other and thus one aids in neutralizing` any tendency of the other to Warp. rFurther- A more,r I preferably choose theifibre of the cardboard discs 2 in such a Way that they will have a minmum coefficient of expansion and that such coefficient shall be as nearly as possible equalto the coefficient. of expansion of the' veneering or thermoplastic coating. Y

The use of a soft, yieldable central layer -or core also results in rendering the record exceptionally flexible and unbreakable in its nature. The looseness of the -fibre of the central core or' layer permits the outer layers to have a slight movement relative thereto and to each other. when a bending force is applied to the record, much in the same vay that a slight slippage occurs between a loosepackage of. paper sheets when the package is bent. The hardness of the two outer layersof my improved record, however, causes the record to spring back into normal shape as soon as 'the bending pressure is relieved. l

In Fig. 2, I have shown a slightly modified construction'in which only two sheets of fibrous material are employed. These sheets are designated by the numeral 4 and are somewhat thicker than the sheets shown in Fig. l. Flach of the sheets 4 is formed from stock, one sido of which only is calendered or hard finished, the other side "being relatively soft and porous. In forming the record body, the two sheets are 'placed with their rough porous faces t0- gether, and are united by a suitable glue or cement which is of suchv a nature as` not to iinpregnate the paper to any substantial extent. A coating of thermoplastic veneering 3v is 'jihen applied to the outer calendered surfaccsfof the sheets t. in the, usual Way.

From the above described method of Inanufacture, there results a structure having a central portion which lis of a loose p0- rous absorbent nature, and outer portions of a harder, denser and more compact character. In this Way. a record having much the same characteristics as that shown in Fig. l is produced.

It Will thus be seen thatthe essential.

nasa/sea feature of my improved record or like article consists in the provoision of a cenyn tral layer or core of soft, fieXible, absorbent material, and that a record constructed in accordance With my invention is bothfree from any tendency to warp and is bendable and substantially indestructible With any ordinary handling, and it is thought that the many' advantages of Vmy improved article will be-readily appreciated Without further discussion.

YVhat I claim is:

` l. A molded article having a central core of relatively loose porous material, superposod layers et' denser, more compact fibrous material, and a surface coating of thermoplastic material.

2. A laminated structure having a body built up of assembled layers of fibrous material, the central portion of said body being softer and more porous than'the outer portions thereof, and a surface coating of thermoplastic material .on said body.

3. A laminated structure having -a body formed of assembled sheets, and a surface layer of thermoplastic material on said body, the inner portion of said body being of a'loose, fibrous nature and more absorbent than the outer portions thereof; l

fibrous i material, a layer of inherently` denser, less porous, stiff fibrous material on each side of said core, and a surface coating I of plastic material.

6. A molded article camprising a central sheet of porous flexible paper of soft, loose texture, a stili sheet of denser and less porous paper cemented to each side of said central sheet, and a thin coating of plastic material covering said denser sheets.

7. A molded articleA comprising a central sheet of porous flexible paper, a stiff sheet of denser and less porous paper cemented to each side of said central sheet, and a thin coating of plastic material covering said denser sheets, the outer surface of said denser sheets to which the coatingis applied beine' calendered.

8. A' laminated article comprising aporou's central sheet of loose fibrousmaterial, a relatively dense sheet cemented to each side ofthe porous sheet, and a suitable surface coating on said outside sheets.

9. A molded article comprising a sheet of soft,.porous paper, a sheet of relatively hard dense paper cemented to each side of said central sheet, the outer surfaces of said dense paper being smooth calendered, and cemented to the interior layer, and a veneer a thermoplastic veneer applied to said ing of thermoplastic material on said outer smooth' calendered surfaces. layers, the inner layer being united to the 10. A laminated phonograph record havadjacent layers by a cement which does 5 ing an inner layer of permanently'soft not impregnate its surface to any substanyielding material to which outer fibrous tial extent, whereby sufiioient relative layers are cemented, whereby the structure movement of said outer and inner layers is rendered flexible. p' v is permitted to render said record iiexible. 1l. A laminated phonograph record lhav- In testimony whereof I afx my signature. l0 ing an inner layer of soft yielding material,

outer layers of relatively dense stii material GEORGE HOWLETT DAVIS. 

